Now here's the embarrassing part...
The one I was looking for was hiding in plain sight over here (posted by Ray MK).
I downloaded and tried several HotPup .pets before, and still can't figure out how I missed it.
Anyway, CatDude and Caneri found it.
(Thanks again, guys!)

And please note, like the 2.14x HotPup, it won't allow writing to NTFS-formatted partitions.
You must use MUT or Pmount for that.
(This was no longer an issue when BarryK did his own 4-series drive icons.)